PHOENIX -- The Diamondbacks' coaching staff was discussing new All-Star Patrick Corbin the other day, and maybe because the Dodgers were coming to town, the talk turned toward another young left-hander, Clayton Kershaw, who is likely to bedevil NL West hitters for some time to come.
"Remember when Clayton Kershaw came up? What did he look like?" manager Kirk Gibson said, flashing back to a thinner version of the Dodgers' most recent Cy Young winner.
"He has filled out nicely."
That the D-backs include Corbin and Kershaw in the same conversation may be the best indicator of how far Corbin has come in his first full season in the major leagues. From rotation candidate to rotation ace in 4 1/2 months.
The numbers tell it. Corbin is 10-1 with a 2.40 ERA and has made 15 quality starts in his 18 appearances. He has given up fewer hits and walks than innings pitched for a WHIP of 0.98, and he has stopped losing streaks of four and three games. He has been the best pitcher not named Kershaw in the division this season.
But they also tell only part of the story. Much has been made of Corbin's mental resilience on the mound, and there is no question that his ability to focus is one of his best traits. His physical maturity also has played a big part, the D-backs believe, one of the reasons the Kershaw comparison came up.
It is easy to forget how young these young major league pitchers are these days and how much physical development remains. Corbin will not turn 24 until three days after his first All-Star Game. Tyler Skaggs, the D-backs' starter on Wednesday, will be 22 on Saturday. Even Kershaw, who broke into the league in 2008, is only 25.
Corbin has gained just a tick on his fastball and slider, according to Fangraphs, which charts major league pitchers, but he seems to be able to get more when he needs it, hitting the 94-95 mph range. He also has a crisper slider after another offseason of training hard, eating right and, for lack of a better phrase, growing up. Corbin, 6-foot-2, was drafted in 2009 out of Chipola Junior College at 165 pounds and is up to about 195 now.
"You look at Patrick and you see he's still growing," D-backs pitching coach Charles Nagy said. "He's still filling out. He's still maturing. You watch that and realize that he still might have some more in the tank."
Corbin has seen positive effects of his added mass.
"Your pitches might be a little bit harder, a little bit sharper and have a little bit more movement," he said. "It's the same exact same (slider) I've been throwing every year, but just because I am throwing maybe a little bit harder, there might be a little more movement."
Corbin has shown more than enough movement for opponents to handle this season, and he has drawn league-wide notice for it. Former Braves third baseman Chipper Jones tweeted "this Corbin dude is pretty nasty!” to his 293,994 followers after Corbin beat Atlanta with seven shutout innings May 14.
Rockies first baseman Todd Helton went one better six days later, telling FOX Sports Arizona that Corbin's slider was the best he had seen after Corbin struck out 10 in a 5-1 complete game at Coors Field on May 20. The Rockies must believe it -- they struck out 10 times in Corbin's last start, a 6-1 Diamondbacks victory on Sunday. He will make one more before the All-Star Game next Tuesday -- on Friday night against Milwaukee.
"He pounds the zone, he moves the ball in and out very well," Nagy said. "His breaking stuff has come a long way -- throwing it for strikes, throwing it for chase pitches. It's a work in progress, but he uses it, and he understands he has to use it. The fastball is better than last year."
And then there is the mental side. Ian Kennedy calls Corbin a silent killer.
"He's a bulldog, he's just quiet about it," Kennedy said. "I've noticed that the command of his slider has been so much better. Quality. He can throw it for strikes, he can throw it for balls. Play it off his fastball. He didn't do that last year."
Miguel Montero sees a cool competitor.
"He looks like Mariano Rivera with the bases loaded and no outs and the tying run on third. He goes out and gets out of the jam without sweating," Montero said.
Wade Miley went through a similar growing process last season, when he went from a rotation candidate in spring training to the staff's biggest winner at 16-11. It breeds an attitude, Miley said, that hitters notice.
"The way Patrick goes out there, the confidence he has, he's ahead right out of the gate," Miley said. "When you are having success, you get that mentality. You're out there and you have the ball and in your hand, they (hitters) don't have a chance. And they see that. Right then and there, you are ahead. They are on the defensive right out of the gate."
Corbin throws his fastball for strikes on both sides of the plate, a knack he demonstrated when he was recalled to join the rotation for good last Aug. 1. Because of that, hitters can look silly swinging at his slider. Nine of his 10 strikeouts against the Rockies on Sunday were on sliders, almost all of them out of the strike zone.
"The hitter may know that he is going to throw a slider, but he doesn't know if it is going to be a strike or not," said Montero, speaking from a hitter's perspective. "The other thing: He mixes pitches. That's even harder, because they don't know what to look for."
Corbin has a 70.3 first-pitch strike percentage, among the best in the majors. Put that with the bulldog Kennedy sees and it gets you to an All-Star Game.
"His poise when he is out there and the adjustments that he makes, it's off the charts," Nagy said. "At that age, you don't see it very often. It's just special.
"And then this year, from Day 1 in spring training, he knew he was competing for the fifth starting spot, and he went out and went about his business. He understood he had to perform. He couldn't really worry about what the other guys are doing. From Day 1, that's what he did, and here we are today."
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